PURPOSE: To investigate the levels of radiation exposure of an operator which may be influenced by the wearing an apron, type of procedure, duration of fluoroscopy and operator's skill during various interventional procedures MATERIALS AND METHODS: Radiation doses were measured both inside and outside the apron(0.5mm lead equivalent) of the operator by a film badge monitoring method and the duration of fluoroscopy was measured in 96 procedures prospectively. The procedures were 30 transcatheter arterial embolizations (TAE), 25 percutaneous transhepatic biliary drainages (PTBD), 16 stone removals (SR), 15 percutaneous needle aspirations (PCNA) and 10 percutaneous nephrostomies(PCN). To assess the difference of exposure by the operator's skill, the procedures of TAE and PTBD were done separately by groups of staffs and residents. RESULTS: Average protective effect of the apron was 72.8%. Average radiation exposure(unit:micro Sv/procedure) was 23.3 in PTBD by residents, 10.0 in PTBD by staffs, 10.0 in SR, 8.7 in TAE by residents, 7.3 in TAE by staffs, 9.0 in PCN and 6.0 in PCNA. Average radiation exposure of residents were 1.9 times greater than those of staffs. CONCLUSION: Radiation exposure was not proportionally related to the duration of fiuoroscopy, but influenced by wearing an apron, various types o[procedure and operator's skills.